Well, compared to SNOBOL4, Icon, and Perl, the string processing capabilities of Rexx are pretty restricted. Even bash has better string handling with it's built in power of regular expressions.|
I guess my point is not that Rexx is a great programming language. But as a batch processing language along the lines of the shell languages, it is easier to read and maintain because the design is much more consistent.
The difference between batch processing languages (bash, dos, rexx, etc...), scripting languages (awk, perl, python, etc...) and general purpose languages (C, Ada, Java, etc...) is a gray one. Most programmers have a tendency to stretch a language either up (in the case of the batch languages) or down (in the case of scripting and general purpose languages).
To me, bash and rexx (and even awk) are intended for quick and dirty shell scripts. Trying to create a large program from them is probably using the wrong tool for the job at hand. The same goes for trying to use perl for everything when it comes to simple system administration.